核压力容器用SA508Gr.4N钢组织遗传性的消除  

Structure inheritance removing of SA508Gr.4N steel for nuclear reactor pressure vessels

作　　者：刘宁[1,2] 刘正东[1,2] 何西扣[2] 杨志强[2] 

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093 [2]钢铁研究总院特殊钢研究所,北京100081

出　　处：《钢铁研究学报》2017年第5期402-410,共9页Journal of Iron and Steel Research

基　　金：国家重点研发计划资助项目(2016YFB0300203)

摘　　要：采用可控速热处理炉对核压力容器用SA508Gr.4N钢消除组织遗传性现象进行研究。为模仿大锻件锻后不同位置晶粒尺寸差异较大现象,对试验钢进行不同温度预粗化处理。设计了A和B两种方案消除试验钢的组织遗传性,结果表明:经方案A即等温退火+亚温正火+正火处理后,得到细小且均匀的晶粒,晶粒等级由2~9级细化为7.5~8.0级,该方案可有效消除SA508Gr.4N钢的组织遗传性现象。观察了等温退火、亚温正火和高温回火后试验钢组织的变化,分析了微观组织变化对消除试验钢组织遗传性的影响。By using heat treatment furnace,the cooling rate of which was controllable,the elimination of structural heredity for SA508 Gr.4Nsteel was experimentally investigated.To simulate the difference of grain size among different positions of heavy forging,pre-coarsening treatment of experimental steel was carried out at different temperatures.Subsequently,two schemes named A and B were designed to remove structure heredity of SA508 Gr.4Nsteel.The results show that after heat treatment of scheme A,consisting of isothermal annealing,inter-critical normalizing and normalizing,fine and homogenous grain can be obtained and the ASTM grain size grade transforms from 2-9to 7.5-8.0,thus the structural heredity of SA508 Gr.4Nsteel can be successfully eliminated.In addition,to investigate the effect of microstructure change on structural heredity removing of experimental steel,the microstructure of this steel after different heat treatment was observed.

关 键 词：SA508Gr.4N钢 预备热处理 组织遗传性 

分 类 号：TL351.6[核科学技术—核技术及应用] TG142.1[一般工业技术—材料科学与工程]